The invention relates to an attachment for a breaking hammer that can be used to crack or split large rocks or used to break concrete slabs.
In the past, large rocks were split or cracked by the use of dynamite. When dynamite was used, it was necessary to drill bore holes in the rock into which a stick of dynamite was placed. An electric cap would have been attached to the stick of dynamite with the wires leading therefrom connected in a circuit containing a switch and a source of electricity.
One of the drawbacks to using dynamite to split or crack large rocks is the danger factor. If the blasting operation is to be performed in an area having buildings or homes in close proximity, it is necessary to cover the rock with a blasting mat to prevent the propulsion of pieces of rocks through the air in an uncontrolled manner. Special risks are created where the blasting operations take place near gas lines. Also if dynamite is being used a special magazine is needed to store or carry it to the job site. The result of the safety danger necessitates the obtaining of special permits to perform the blasting operations and also necessitates costly liability insurance. Liability insurance premiums are a prime factor in the high cost of conventional explosives use.
Another drawback to the use of dynamite to split large rocks is that it requires a trained expert to set the charge and explode it. In many cases this necessitates the hiring of a blasting contractor and delays may result from his having to fit your job into his schedule. Also special time consuming procedures are normally observed to insure safety and one of these is the requirement of moving personnel and/or equipment to a safer place while the blasting operation takes place. This in general results in production down time since the general work of the labor force is normally curtailed while the blasting operation takes place.
A third drawback to the use of dynamite as opposed to a machine or tool that will perform the same result is the cost factor. Currently a blasting cap costs approximately $0.70 each a charge of dynamite with the required useful force would cost about $0.15. Once the blasting operation occurs, these materials are lost and cannot be used again. If a tool or machine is utilized to perform the operation, it can normally be used again and again.
A fourth drawback to the use of explosives for cracking or splitting large rocks is the relatively long time required to perform the preparation work. The charges are normally set in holes which have been drilled approximately four feet into the rock. The time required for drilling the first two feet of the hole takes about four minutes. To perform the next two feet of drilling requires more than twice that amount of time. One reason for this is the loss of hammering power due to the dampening effect on the longer shaft. An additional factor is the loss of sufficient air volume and pressure to exhaust chips from the bottom of the hole resulting in loss of drilling efficiency due to the padding effect caused by the chips that aren't removed quickly enough. When the long drilling time for one of these holes is multiplied times the number of holes that would be drilled in cracking a large rock, the total time becomes very substantial.
A fifth drawback to the use of dynamite for splitting large rocks is the environmental aspect. The use of dynamite results in the release of poisonous gases into the air. Also it results in dust being stirred up into the atmosphere.
It is an object of the invention to provide a device for splitting large rocks that will not throw debris or send massive uncontrolled shock waves throughout the surrounding area.
It is also an object of the invention to provide a device for splitting large rocks that will eliminate the use of dynamite with its attendant dangers.
It is also an object of the invention to provide a device for splitting large rocks that will not necessitate the movement of personnel and/or equipment to a safer place while the device is in operation.
It is also an object of the invention to provide a device for splitting large rocks that would not disturb the surrounding area or loosen the walls of a ditch or tunnel in close proximity thereto thus exposing personnel to unnecessary cave-in hazards.
It is also an object of the invention to provide a device for splitting large rocks that does not require the person performing the operation to have extensive special knowledge such as is required of an explosive expert.
It is also an object of the invention to provide a device for splitting large rocks that does not release any poisonous gases or throw any dust into the air.
It is a further object of the invention to provide a device for splitting large rocks that will eliminate the need for liability insurance premiums such as are necessitated by the use of dynamite.
It is an additional object of the invention to provide a device for splitting large rocks that can be used over and over again thereby cutting down the cost of such an operation.
It is an additional object of the invention to provide a device that can be used to break concrete slabs and one which will allow the operator to have directional control over the fracture produced by the device.